An isolator for an acoustic logging system includes an outer housing surface, a bore, an outer bore surface, and a first isolator feature positioned between the outer housing surface and the outer bore surface to reduce a collar wave transmitted by the acoustic source.

Acoustic characterization and mapping of flow from a perforation zone of a well. As a wireline probe containing acoustic sensors moves through the well, the acoustic sensors record acoustic pressure measurements of flow for each perforation in the well casing. The acoustic data is recorded and compiled into a three-dimensional flow model showing flow of hydrocarbons within and/or out of perforation tunnels. The three-dimensional flow models generated can be combined with historical data to form four-dimensional models illustrating flow over time, and both the three and four-dimensional models can be used to determine effectiveness of perforation charges as well as future flow from the well.

Acoustic characterization and mapping of flow from a perforation zone of a well. As a wireline probe containing acoustic sensors moves through the well, the acoustic sensors record acoustic pressure measurements of flow for each perforation in the well casing. The acoustic data is recorded and compiled into a three-dimensional flow model showing flow of hydrocarbons within and/or out of perforation tunnels. The three-dimensional flow models generated can be combined with historical data to form four-dimensional models illustrating flow over time, and both the three and four-dimensional models can be used to determine effectiveness of perforation charges as well as future flow from the well.

This disclosure describes systems, methods, and apparatuses for preventing wireline sticking during hydraulic fracturing operations, the system comprising: a sensor coupled to a fracking wellhead, circulating fluid line, or standpipe of a well and configured to convert acoustic vibrations measured in fracking fluid in the wellhead, fluid line, or standpipe into an electrical signal in a time domain; a memory configured to store the electrical signal; a converter configured to access the electrical signal from the memory and convert the time domain electrical signal into a frequency domain spectrum; a machine-learning system configured to classify the current frequency domain spectrum as associated with increasing wireline friction, the machine-learning system trained on previous frequency domain spectra measured during previous wireline operations and previously classified by the machine-learning system; and a user interface configured to return an indication of the increasing wireline friction to an operator of the hydraulic fracturing operations.

The disclosure relates to a system, downhole device and method for monitoring a wellbore, in particular in a lateral section, during stimulation, with an equipment enabling retrieval in many conditions. The method includes monitoring the wellbore with a distributed fiber optic sensor to determine one or more characteristics of the stimulation operation using detected backscattered optical signals on the distributed fiber optic sensor. The cable is retrieved by exerting a traction force. The disclosure also relates to a downhole device for receiving a cable and retainers to maintain the cable and having a weakpoint configured to break when subjected to a force along the longitudinal axis greater than a predetermined threshold. The system comprises the cable having the distributed fiber optic sensor, the downhole device and a surface monitoring system for determining the characteristic of the stimulation operation using detected backscattered optical signals on the distributed fiber optic sensor.

The disclosure relates to a system, downhole device and method for monitoring a wellbore, in particular in a lateral section, during stimulation, with an equipment enabling retrieval in many conditions. The method includes monitoring the wellbore with a distributed fiber optic sensor to determine one or more characteristics of the stimulation operation using detected backscattered optical signals on the distributed fiber optic sensor. The cable is retrieved by exerting a traction force. The disclosure also relates to a downhole device for receiving a cable and retainers to maintain the cable and having a weakpoint configured to break when subjected to a force along the longitudinal axis greater than a predetermined threshold. The system comprises the cable having the distributed fiber optic sensor, the downhole device and a surface monitoring system for determining the characteristic of the stimulation operation using detected backscattered optical signals on the distributed fiber optic sensor.

A system for measuring fluid flow in a wellbore is provided. A probe includes at least a heater. A fiber optic cable is connected to the probe. The system is programmed to perform operations including: changing an output of the heater to thereby change a temperature of drilling fluid moving over a fiber optic cable; measuring a strain on the fiber optic cable caused by changing the temperature of the drilling fluid; preliminarily determining a velocity of the drilling fluid from the measured strain; measuring at least a second parameter of the drilling fluid; adjusting the preliminary determined velocity based on the measured at least a second parameter to yield an adjusted velocity; and determining a flow rate of the drilling fluid based on the adjusted velocity.

The present invention provides an intelligent geophysical data acquisition system and acquisition method for shale oil and gas optical fiber. A pipe string is arranged in a metal casing, and an external armored optical cable is fixed outside the metal casing; an, internal armored optical cable is fixed outside the pipe string; the external armored optical cable comprises a downhole acoustic sensing optical cable, two multi-mode optical fibers, a strain optical cable and a pressure sensor array, and further comprises horizontal ground acoustic sensing optical cables arranged in the shallow part of the ground according to an orthogonal grid, and artificial seismic source excitation points arranged on the ground according to the orthogonal grid.

The present invention provides an intelligent geophysical data acquisition system and acquisition method for shale oil and gas optical fiber. A pipe string is arranged in a metal casing, and an external armored optical cable is fixed outside the metal casing; an, internal armored optical cable is fixed outside the pipe string; the external armored optical cable comprises a downhole acoustic sensing optical cable, two multi-mode optical fibers, a strain optical cable and a pressure sensor array, and further comprises horizontal ground acoustic sensing optical cables arranged in the shallow part of the ground according to an orthogonal grid, and artificial seismic source excitation points arranged on the ground according to the orthogonal grid.

This invention relates to the method of assessing the integrity of primary and secondary barriers in the interval where a cement plug is to be installed in the well proposed for abandonment. The technical result of the invention is to enhance the accuracy of wellbore barrier integrity assessment. The method of well integrity assessment below production packer, including inner and outer casings, tubing string and production packer installed inside the casing, and cement sheath and adjacent rocks, comprising the following phases: Identification of the target zone for cement plug installation; installation of a temporary cement plug below the target zone; pressure testing and assessment of tubing and below-packer zone integrity based on steady pressure data or pressure variation in time; creation of a perforation zone in casing and cement below production packer in the target zone; conducting a logging survey including noise, temperature, defectoscopy, and production logging in the target zone during a repeat pressure test; issuance of a findings report on casing and cement integrity and subsequent installation of a cement plug for well abandonment, including rigless operations or remedial cementing at designated locations where integrity failures have been identified on the basis of logging data.